As the title states, I have no idea which colleges I should apply for if I want to go into math. I’m not picky about location, size, or cost, but a decent ranking would be somewhat nice. I have a 1510 SAT and 3.70/4.20 GPA if that helps anyone. If anyone could do some suggestions for me that would be nice. Thanks!
Why is your state flagship (public) university not good enough?
The Princeton Review suggests colleges for math in its sampling “Great Schools for Mathematics Majors” (Harvey Mudd, MIT, UChicago, Caltech, Haverford, Harvard, Hamilton, Bowdoin, Reed, Rice, Carleton, Grinnell, Macalester, St. Olaf . . .). You could trim the high reaches from this group and potentially still have a few from which to choose.
What is a ‘decent’ ranking?
What is your plan post-university?
What level of math will you have going into college?
Does ‘not-picky about…cost’ mean that your parents can & will pay up to $70,000/year?
Most universities in the top 50 will be great for math, and most in the top 100 will prepare you for anything mathy you want to do after college. Most of the selective LACs will as well, with the caveat that the smaller ones may have more limited course offerings.
Given what you have said so far, it would be easier to identify what colleges would not be a good idea for math 
Really, to be helpful, more info is needed.
I’ll have taken Multivariable Calculus, Calc AB and BC, and AP Stats by the time I am finished with High School. My mom really values the name of the college because she thinks it will help in job applications. I am not sure about my plan for post college yet.
You would be likely to begin your college math studies by taking linear algebra (a gateway course to higher math) as well as perhaps a second-level statistics course (or possibly by repeating in a college environment a course you have taken already). Based on this, you can explore a wide range of college options.
Post graduation plans (PhD, high school teaching, finance/actuarial, operations research, etc) can matter, since some math departments emphasize offerings good for some plans but not others.
At some schools, subjects like statistics may be separate departments, but may be under math at others.
You need to think about what you want from college besides ‘math’. All universities and colleges are going to have a math department, whether it is ‘good enough’ depends on your goals and interests. Do you want to major in math? If so what are your interests? However a strong math background is the foundation of STEM degrees and economics. The fact that you took MV in HS, doesn’t mean you will want to major in math. That math interest will help you in many other degrees also.
Also be realistic about that 3.7 UW GPA. Just because you have a 1500+ SAT, don’t ignore your GPA and overshoot–meaning only apply to schools and honors programs that are very hard to get into. Your ECs will also matter, at some schools they matter a lot, while at schools that have rolling admission or auto-admit based on scores/GPA they won’t matter as much.
If you go to a smaller LAC you might not have as many choices for Math classes compared to going to a larger school with a graduate program in Math. Very advanced students might run out of classes which doesn’t appear to be your case.
Other than that I would look at everything else. As others have said basically every school has a math program so other factors should drive your decision.
@Dolemite Math is a core department at a lot of top LACs, such as Williams. If OP ends up going to one of those, they shouldn’t have an issue.
My daughter majored in Math. But she knew she wanted to be a math teacher. So it was important not to spend tons of money on a college. So she went to a public college that had the opportunity for a masters in teaching.
So you should think abou twhat you want to do with math.
Teach?
Wall Street Quantitative?
Actuary?
Cryptographer.
Mathematician. …
Economist. …
Actuary. …
Financial planner. …
Investment analyst. …
Statistician. …
Operations research analyst.?
And then look at schools that are affordable and have other courses of interest and internship opportunities.
@writingpumpkin03 It’s something to be concerned with if you are very advanced at math especially at the smaller and lower ranked LACs. I know of a student that even turned down Williams for a larger school with grad programs due to this concern but this is a student that’s ranking high on the Putnam as a sophomore so it’s rare but nonetheless it doesn’t take that long to look at the classes offered.
Perhaps more specifically, any college with a small math department. Note that math departments do have to use some of their teaching capacity on large numbers of non-math majors who need math courses for their majors.
Yes, a very advanced student in math who wants to be a math major can easily and should check the math department’s offerings.
@Dolemite Of course, there are always going to be prodigies, and if OP is one then they’ll have to do research about different departments. But Williams and other LACs generally have excellent math departments.